Smog dims the city of lights; our streetlamps might be driving away bats; and everyone's least favorite infectious disease, measles, has popped up in yet another city. It's all in this week's all-Gizmodo look at What's Ruining Our Cities.

Smog is ruining Paris

This week's smog alert is not coming from Beijing… it's Paris? Due to unusually warm spring weather, much of France is blanketed in noxious and dangerous air pollution, which is made worse by the use of diesel-fueled cars (which make up 60 percent of the country's vehicles). However, there is one silver (yellowish grey?) lining: It's gotten so bad that officials in Paris are taking the radical next step of making public transportation, bike shares, and electric car shares free to use all weekend. [Gizmodo]

There was a much-ballyhoo'd article floating around the internet this week about how bats don't like city lights (obviously, they're bats!) so they might not be doing the best job when it comes to spreading seeds that might help regenerate deforested areas near light-polluted areas. But the real issue here is not as much urban light, it's deforestation itself and our generally abusive behavior towards the rain forests? Because let's be honest: Chainsaws are really what's harming the rain forest right now. [Gizmodo]

Measles are ruining more American cities

Just a few weeks after San Francisco had a measles scare on public transit, as of last Friday, 16 cases of the highly-contagious respiratory virus had been reported in New York City. Despite having been officially "eliminated" in the United States since 2000, measles can still make its way back into communities when people bring it from overseas. Which means in addition to these cities, now measles have cropped up everywhere from San Diego, to Boston to a suburb of Vancouver. The former is a particularly scary case; 100 cases have shown up recently. [Gizmodo]